Deck 13: Spinal Region

Question 1

Klumpke's paralysis is the result of which of the following?

A)Avulsion of the C5 to C6 ventral roots
B)Mechanical irritation of the C7 to C8 dorsal roots
C)Traction force applied to the cervico-occipital region
D)Lesion of the dorsal root ganglion because of a herniated disk
E)Avulsion of the C8 through T1 motor nerve roots

Answer 1

E
Explanation: Traction on the abducted arm can cause avulsion of the motor roots of C8 and T1,resulting in Klumpke's paralysis.Loss of lower motor neuron output from the C8 and T1 spinal levels results in paralysis and atrophy of the hand intrinsic muscles and the long flexors and extensors of the fingers.

Question 2

Which one of the following exits the spinal cord through the ventral root?

A)Sensory neurons
B)Sympathetic preganglionic neurons
C)Lower motor neurons
D)Both B and C

Answer 2

D
Explanation: Both sympathetic and parasympathetic preganglionic neurons exit the cord via the ventral root.The ventral horn is primarily cell bodies of lower motor neurons whose axons exit the spinal cord via the ventral root.

Question 3

Dorsal rhizotomy is the selective surgical ablation of which of the following?

A)Dorsal horn neurons
B)Posterior commissural axons
C)Dorsal roots
D)Dorsal columns
E)Nucleus dorsalis

Answer 3

C
Explanation: Dorsal rhizotomy is selective surgical ablation of the dorsal roots.The purpose of the surgery is to decrease or eliminate hyperreflexia by interrupting the afferent limb of the stretch reflex.The procedure is selective because individual dorsal rootlets are stimulated electrically before ablation to determine whether activity in that specific dorsal rootlet contributes to hyperreflexia.If stimulating the rootlet does not contribute to hyperreflexia,the rootlet is left intact to provide somatosensation.

Question 4

Cerebrospinal fluid is found between which one of the following layers of the meninges?

A)Pia mater and arachnoid
B)Arachnoid and dura mater
C)Pia mater and dura mater
D)None of the above

Question 5

Which one of the following is NOT a sign of an upper motor neuron lesion?

A)Muscle paresis
B)Hyperreflexia
C)Muscle fasciculations
D)Positive Babinski's sign
E)Spasticity

Question 6

After a complete spinal cord injury affecting S2-4,a bladder that cannot be emptied is which of the following?

A)Hypertonic and hyperreflexive
B)Flaccid and paralyzed
C)Spastic
D)Autoreflexive
E)None of the above

Question 7

Complete spinal cord lesions above which one of the following levels results in long-term ventilator dependence?

A)C4
B)C5
C)C6
D)C7
E)All of the above

Question 8

Reciprocal activation of a stepping pattern generator (SPG)is thought to be coordinated by signals conveyed in the:

A)DCML.
B)Golgi tendon organs (GTOs).
C)Posterior commissure of spinal cord.
D)Anterior commissure of spinal cord.
E)Ventral horn gamma motor neurons.

Question 9

The lateral horn contains which of the following?

A)Preganglionic parasympathetic cell bodies
B)Preganglionic sympathetic cell bodies
C)Postganglionic parasympathetic cell bodies
D)Postganglionic sympathetic cell bodies

Question 10

Loss of pain and temperature sensation in a capelike distribution over the shoulders,lower limb paresis,hyperreflexia,and loss of bowel and bladder function are characteristic of which of the following?

A)Multiple sclerosis
B)Cervical spondylosis
C)Meningomyelocele
D)Syringomyelia
E)Erb's paralysis

Question 11

Loss of descending sympathetic control as a result of complete spinal cord lesions above T6 result in which of the following?

A)Orthostatic hypotension
B)Autonomic dysreflexia
C)Poor thermoregulation
D)Both A and B
E)A,B,and,C

Question 12

Which one of the following spinal cord laminae process noxious sensory information?

A)Marginal layer
B)Substantia gelatinosa
C)Nucleus proprius
D)Both A and B

Question 13

Vertebral canal stenosis is associated with which one of the following?

A)Narrowing of the vertebral canal caused by bone growth or tissue hypertrophy
B)Compression of neural and vascular structures of the spinal cord
C)Radiating pain with numbness and loss of proprioception
D)All of the above
E)None of the above

Question 14

Interneurons serve which one of the following functions?

A)Modulation of sensory information
B)Coordination of motor activity
C)Autonomic regulation
D)All of the above

Question 15

Autonomic dysreflexia is characterized by which one of the following?

A)Abrupt decrease in blood pressure because of sympathetic vasoconstriction
B)Abrupt increase in blood pressure and pounding headache
C)Profuse sweating below the level of the lesion
D)Excessive activation of the parasympathetic nervous system
E)Excessive shivering associated with hyperthermia

Question 16

Which one of the following spinal cord laminae contains cell bodies of lower motor neurons?

A)VIII
B)IX
C)X
D)Both A and B